So much coal dust escapes from the open-top rail cars used for transporting coal that it can create safety problems for rail traffic. Coal dust deposits sometimes cause spontaneous fires, and in 2005, for example, coal dust that had accumulated in ballast, the layer of crushed rock that supports rail tracks, caused derailments. Given the coal export industry’s designs on the Northwest, it is important for residents to know more about the coal dust hazard.

Industry research is suspect

As much as 3% of a coal car’s load, which is typically 100 tons or more, can blow away in transit.

If shippers wished to reduce or prevent coal dust from escaping, they could do so by filling cars less full or covering them with tarps or chemical sprays. However, these measures run up the cost of moving coal, so coal shippers prefer not to employ them. A March 2011 ruling from the US Surface Transportation Board, which oversees railway operations, allowed BNSF to require coal shippers to control dust, but many believed the controls would be ineffective. Coal shippers appealed the decision, blaming BNSF’s operating procedures for the spread of coal dust and arguing that the railway’s dust reduction goals were unrealistic and based on “junk science.” The government ruled in favor of the railroads, however, finding that it is possible to control coal dust by means of shaping the coal when it is piled into a railcar and applying chemical topping agents to the coal—the shippers’ responsibility, then, and not the railways’.

Nonetheless, there are good reasons for skepticism about the industry’s research, the so-called “Super Trial” studies, including the fact that much of it is neither peer-reviewed nor available for public inspection. Moreover, the industry’s tests did not evaluate the effectiveness of dust-control measures over long distances, a potential problem for regions like the Northwest that are relatively far from coal mines.

Complicating matters for the Northwest, Powder River Basin (PRB) coal—the type that would be exported from proposed terminals in the region—is notoriously difficult to handle. One technical analysis finds that “PRB coal is extremely friable and will break down into smaller particles virtually independent of how the coal is transported or handled.” According to the study’s authors, “PRB coal represents the extremes of handling problems.”

The same analysis found that:

Spontaneous combustion of coal is a well-known phenomenon, especially with PRB coal. This high-moisture, highly volatile sub-bituminous coal will not only smolder and catch fire while in storage piles at power plants and coal terminals, but has been known to be delivered to a power plant with the rail car or barge partially on fire… [emphasis mine].

Outside of confined environments, PRB coal does not spontaneously explode or burst into full flame, but under the wrong conditions it can self-ignite and burn slowly even while it is riding the rails—a troubling proposition for railroad workers and communities along the tracks throughout the Northwest.

Great article! Looked this up after watching the train transporting coal under a bridge in the Pacific Northwest. I believe our government could create a few hundred jobs by enforcing standards to control the transport of necessary yet hazardous materials.

I have puzzled over the jet black dust that cloggs our highrise buildings air filters. This black dust gets through the filters and cloggs a second filter I installed in the air vent into our corridor. When i opened the vent i thought i must have installed a black air filter it was soo black. It puzzled me. Then just by chance i flew in a small plane over a nearby coal shipping dock some miles south ditectly across the water and often upwind of our building. The size of the operation was an eye opener. It was a direct line to the point where I live and where the riaing air would cause it to drop the heavier particulate matter drawn up by the wind. I am shocked. When I first moved here I had serious bronxhitus several times a year. I suspected many things. It has improved but the air quality disturbs me. I am not even sure who to bring this to the attention of.

Very interesting article. Is Sightline following the rollover/derailment investigation of the AMTRAK train at Chambers Bay on July 2? Could rail ballast contamination from coal trains be the cause? Coal dust is slippery stuff. From the photos, one side of that rail bed appears to have dipped.

I was sitting a few autos back from a rail crossing in Kent, WA a few days ago as a coal train was passing by. Not sure about BSNF’s proclamations that shaped loads with surfactants on them is working to minimize coal dust. Many of the cars on that train had very full uneven looking loads in them. I could see several places on top of the piles that appeared to have been disturbed and moving around during transport. These coal piles in the rail cars are not staying in the initial angle of repose during shipment. I am worried about too much coal dust in downtown Kent. More testing needs to be done.

Nev,
With respect to your black dust that clogs the building air filters. I know in Seattle there is a lot of diesel exhaust particulates from Metro buses that gets all over things. My daughter had an apartment on Capital Hill that was on a bus route. Her outside balcony floor and furniture always had black soot deposited on them. My wife who is an HVAC engineer and who has worked on many air handling projects in downtown Seattle says that is probably the biggest cause of the black dust. Hopefully, we will get more electric buses in the future and cleaner diesel for ships in that come into Elliot Bay.

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